South Carolina leaned on its newcomers of Gill and junior college transfer Brenton Williams, who added 13 points. All 10 Gamecocks who played also scored.
The Gamecocks made 30-of-59 shots, the first time they have shot better than 50 percent in 17 games.
Western Carolina turned the ball over 19 times. Trey Sumler and Harouna Mutombo each led the Catamounts with 11 points.
South Carolina started off missing six of its first seven shots, but the Gamecocks didn't struggle much after that. South Carolina started pressing Western Carolina about midway through the first half, leading to two quick buckets by Williams and a time-out from the Catamounts, who won their division in the Southern Conference last season.
Western Carolina then hit back-to-back 3-pointers to tie the game at 16 with nine minutes left in the first half, but the Gamecocks finished the half on a 19-9 run.
By the second half, it was highlight time for the Gamecocks. Gill had an alley-oop that turned into a layup that put South Carolina up 63-40 with 6:26 to go. Brian Richardson brought the sparse crowd to its feet with a one-handed jam with 4:45 left that put the Gamecocks up by 24 points.
South Carolina got plenty of help from everyone. Nine of the 10 players who played at least 10 minutes scored as coach Darrin Horn shifted line-ups and wasn't afraid to substitute out his entire team. The Gamecocks bench scored 38 points.
South Carolina won its 11th straight opener, while Western Carolina fell to 0-8 against the Gamecocks. Western Carolina coach Larry Hunter was denied his 600th career win.
The Gamecocks went 14-16 last season, losing nine of their last 10. Then came an offseason full of turmoil. Leading scorer Bruce Ellington decided to moonlight on the football field, meaning he'd miss several games.
Expected starter Murphy Holloway transferred away without ever taking the court. South Carolina was picked to finish last in the Southeastern Conference.
South Carolina wins opener
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